When Michael Keck was hospitalized with a heart infection at 25 years old, he asked his wife to donate his brain to a brain bank for research when he died.

Keck had dropped out of college when he started failing courses, started verbally and physically abusing his wife, had trouble staying awake during the day or eating as much as usual, and generally felt unworthy.

During 16 years of playing football, he had suffered at least 10 concussions. His symptoms pointed to depression or post-concussive syndrome. So when Dr. Ann McKee, chief of neuropathology at the VA Boston Healthcare System, saw his brain after he died of a heart attack, she was stunned. She saw signs of chronic traumatic encephalopathy, or CTE, which can only be found after death, that were striking for someone so young.

"I'm always surprised to see this type of disease in someone so young," said McKee, who is also a professor of neurology and pathology at Boston University School of Medicine. "At age 25, brains can still be developing, pruning synapses. So I'm always taken aback. I can't get used to it."

The CTE diagnosis was not a surprise, however, to one person: Keck's wife.

"It's what he wanted to prove to everybody," Cassandra Keck told the Associated Press last year. "He was really suffering, and nobody believed him."

His case study, published in JAMA Neurology this week, may do more than simply prove him right: It lends a sense of urgency to find a way to diagnose CTE during life, researchers said.

"There are huge efforts going on all over the country to be able to diagnosis it," McKee said, from looking at biomarkers that could be identified in blood samples to neuroimaging techniques.

Putting Keck's case in perspective is difficult because doctors still don't know how prevalent CTE is. One thing scientists have learned in the past 10 years, since the first case of CTE was diagnosed, is that most people who get concussions recover quickly, and most of those who suffer from post concussive syndrome for longer periods still do not get CTE.

Doctors and scientists would love to be able to parse out what puts people like Keck at risk, to be able to advise them of their unique odds, to avoid the experience Keck had of presenting non-specific symptoms to doctors who attributed them to other things, such as depression or chronic headaches.

"Not everybody gets this disease, so what was it about him?" said Dr. James Noble, an assistant professor of neurology at Columbia University Medical Center who wrote a commentary accompanying the case study. "Was there a way we could have known?"

Somehow, in other words, it seems likely that Keck was particularly susceptible to the disease.

"It could be genetic modifiers, family history, etc.," McKee said. "There are bound to be other factors that make the risks higher or lower, and we're proceeding full speed ahead to try to understand."

A neuropsychological evaluation unique to Keck's case helped, for example: While the evaluation showed impaired learning and difficulty planning and organizing, his memory was intact, something which could rule out an otherwise similar disease such as Alzheimer's. Keck's case was also unusual because he developed symptoms during his football career, whereas most known cases had a latent period after their athletic or military career, McKee said.

Still, the take-away from this case should be that "our conventional means of diagnosing concussion and CTE is really limited," Noble said. "Right now the way we diagnose concussions is entirely contingent on the players telling us what happened. (It would be helpful to have) better methods of diagnosing it at the moment. What biomarkers can we use after the game or during the game to tell us if someone is injured?"

Noble also calls for a monitoring program at all levels of athletics, similar to the tracking system the NCAA uses. Ideally, he said, someone injured in a peewee league would have a record that followed her to high school and college. It may also allow researchers to discern patterns such as regional differences or approaches to practice.

It's been about 10 years since the first case of CTE was diagnosed posthumously. It's reasonable to think, Noble and McKee agreed, that in the next 10 years, there will be a way to diagnose and help patients while they're living.

"If someone dying so young isn't inspiration to make us want to learn more, what is?" Noble asked.

Last week, the 2011 NFL regular season officially kicked off. While the athletes, the atmosphere and the sense of team pride draw fans to the sport, the physicality of the game is undoubtedly one of football's big draws.
Although football is the hard-hitting sport popular in America today, it is by no means the most physical game ever played.
From long-dead spectator sports like gladiator combat to the ancient incarnations of the sports now known as lacrosse and polo, explore some of the most violent sports in history in this slideshow.

In what might be the most well known spectator sport of the Roman era, gladiator combat pitted armed men, typically slaves and criminals, against each other as well as wild beasts, including lions, bears, and more.
Although injuries and fatalities are common with this kind of blood sport, gladiators could earn substantial sums through victory. Games featuring gladiators were hosted not only for ritual purposes, such as religious celebrations or funerals, but also as a means for the rich to show off their power.
Around the 4th century, the increased need to protect the empire from outside invaders as well as the rising influence of Christianity led to a decline and the eventual disappearance of the sport entirely.

Similar to gladiator combat, venatio were a sport that pitted armed men against wild and often exotic animals.
The matches were hardly even. In a single day, thousands of animals could be slaughtered by only a handful of hunters. In fact, although lions, tigers, bears, and elephants were included in the event, non-aggressive creatures, such as rabbits and deer, were also included in the games.
On the other side of the coin, animals were often also used to inflict punishment. A common execution of criminals and most famously Christians often involved mauling by a large beast like a lion or bear.

Today, polo is known as a gentleman's activity. The team sport is so synonymous with high society that a polo player on horseback has even become the symbol of a popular fashion brand.
But when polo was first played by Persians starting in the 5th century, it was anything but a civilized game. Originally, toughened cavalries played the sport to hone their horseback battle skills.
Eventually, Iranian nobility picked up on the activity and the game has been identified with upper-class leisure ever since.

These days, racquetball is a fairly genteel sport. Like polo, it's also associated with a refined, rather than purely physical athlete.
But early forms of the sport were much more violent. Consider the sport played by indigenous tribes, including the Maya and the Inca, throughout ancient Central and South America.
Although the exact rules of the game are a mystery, courts and rubber balls left behind by these tribes reveal what the sport entailed. Like the ancient sport of polo, this ball game simulated battle, but ancient Mesoamerican tribes took it one step further: With games involving religious rituals, losers wouldn't simply shake hands and go home; they would be sacrificed to the gods. Some historians have even suggested that dismembered heads were used as balls in some ritualistic games.

Before lacrosse was a popular sport among prep schools in the mid-Atlantic and northeast United States, Native Americans throughout North America played an ancient version of the game that traces back as far as 2,500 years ago.
Back then, lacrosse wasn't played for fun, but rather was part of a religious ritual simulating war. The goal wasn't to have fun, but rather honor their gods and toughen up the young warriors. Games could go on for days and might include hundreds of players on each side.
Their version of the game didn't include pads and helmets. In fact, the earliest players didn't have any protection at all. Rather than carrying metal or graphite sticks with nets, their ornately decorated sticks were made out of wood and possibly deer skin.

Any film buff has seen the famous chariot race in 1959 classic epic film Ben-Hur. Although the sport still remains alive today, the height of its popularity occurred between the ancient Greek and later the Roman era in which the film is set.
For both the drivers and the horses, chariot racing could be particularly hazardous, frequently causing injury and death. However, it was also one of the more popular spectator sports of its time.
Victory often meant large winnings for those skilled and lucky enough to win races. In fact, according to an estimate published in the historical magazine Lapham's Quarterly, the highest paid athlete in history was an ancient Roman charioteer.

For what might be the oldest combat sport ever played, dating back as early as the 13th century B.C., wrestling may seem like a fairly tame entry compared to the other sports in this list.
However, consider this: For much of its history, wrestling was an event in which participants were entirely nude. Those locks, falls, and pins hurt a lot more without any clothes.
On a more serious note, early forms of wrestling did not always include what is traditionally understood as "Greco-Roman wrestling." One variant, a martial art known as Pankration, involves a combination of boxing and wrestling techniques. This form of combat did not have any of the same rules as traditional wrestling and could result in serious injury for participants.

Like many early sports appearing on this list, jousting is an activity derived from warfare.
The medieval incarnation of this game involves two heavily armored knights riding at each other at full speed while aiming a wooden lance at an opponent in order to knock him off his horse.
Although jousting was a sport steeped in rules and pageantry, it was nonetheless dangerous for even the most well protected participants. Injuries and even deaths were common.

Fisherman's jousting is a sport that originated in ancient Egypt and is still played to this day.
Here's how it works: Two fishermen on small boats approach each other head on and try to knock each other from their vessels.
Although preventing injury in this sport is easily achieved these days, during the time of the pharaohs of ancient Egypt, most participants of this sport didn't actually know how to swim. This made drowning a common danger for any losers.

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